Wide bandgap (WBG) semiconductor power electronics (PE) constitute an emerging new set of technologies for the switching and conversion of electrical power, which collectively is poised to transform US and world energy economics. WBG PE will accelerate the electrification of transportation, the adoption of efficient building technologies, and the flexible integration of renewable energy sources for a responsive smart grid. While not yet fully developed, WBG power device performance already far exceeds that of the 50-year-old incumbent silicon (Si) technology. Replacing Si-based PE with WBG-based PE can reduce losses significantly, while also reducing size, weight, and cooling requirements.
As the name implies, a “wide bandgap” semiconductor is one having a large bandgap energy. Typically, semiconductors with bandgap energies larger than 2 eV are said to be “wide bandgap.” The AlN—GaN—InN system (i.e., AlGaN semiconductors) of WBG semiconductors has been extensively studied for fabricating light-emitting devices for wavelengths shorter than green. There are many potential applications of nitride-semiconductor power electronic devices because of their high breakdown electric field and electron drift velocity at high electric fields. These characteristics of high voltage and high carrier density are particularly effective in enabling the fabrication of smaller devices delivering high output power at high frequencies.